• Share:
Making Sense of Lumber Dimensions

Don't be confused by “nominal” board dimensions when you buy lumber or read plans. We show you the quick translation to “actual” numbers.

By the DIY experts of The Family Handyman Magazine

Nominal vs actual dimensions

If you find reading plans confusing, or have trouble identifying the exact dimensions of wood at a lumberyard or home center, read on. Most lumber is sold in “nominal” (in name only) sizes such as 1x3, 2x4 and 4x4. But these sizes are not the actual dimensions of the wood. The chart below shows the actual dimensions of lumber when it is dry (when wet, it will be slightly larger). This handy chart will help you translate the nominal into the actual (dry). After a while, you'll get the hang of it.

Additional Information

Back to Top

Comments from DIY Community Members

Share what's on your mind and see what other DIYers are thinking about.

1 - 2 of 2 comments
Show per page: 20   All

October 19, 12:07 PM [GMT -5]

Yes, I noticed my incorrect math.
"5.75" width..." should be 5.25"
Hence the reason I am looking for dimension help.
God bless.

October 19, 12:02 PM [GMT -5]

This was helpful, thanks. 
You listed Thickness as 1/2" less than indicated at stores.
And Width in inches is 3/4" less than indicated.

Does this "Inches" conversion also relate to the Feet of length that stores indicate.
For instance a 2 x 6 x 8 is actually:
1.5" x 5.75" with 8' length 
or 7ft 11.25" length?

+ Add Your Comment
closeX

Add Your Comment

Making Sense of Lumber Dimensions

Please add your comment
closeX

Log in to My Account

Log in to enjoy membership benefits from The Family Handyman.

  • Forgot your password?
Don’t have an account yet?

Sign up today for FREE and become part of The Family Handyman community of DIYers.

Member benefits:

  • Get a FREE Traditional Bookcase Project Plan
  • Sign up for FREE DIY newsletters
  • Save projects to your project binder
  • Ask and answer questions in our DIY Forums
  • Share comments on DIY Projects and more!
Join Us Today
closeX

Report Abuse

Subject
Reasons for reporting post

Free OnSite Newsletter

Get timely DIY projects for your home and yard, plus a dream project for your wish list!

Follow Us

Featured Product

Buy Now